Real world experience of the burden of infection in myeloma

ABSTRACT

The treatment landscape in myeloma has rapidly changed over the last few years with the advent of an ever increasing number of funded novel therapies. At the same time, the COVID-19 pandemic has caused a paradigm shift in the burden of infection within the community. Clinical trials often exclude older and more comorbid patients and so there is a paucity of data of the effect of infection on patients with myeloma in the 'real world'. We performed a restrospective audit of all patients with myeloma admitted with infection to our level 2b haematology centre over a 3-year period from November 2019 to November 2022. We collected data on patient demographics and characteristics, infection status, microbiology results, length of stay and outcome of admission. During the audit period there were 87 admissions from 52 patients. The median number of admissions per patient was 1 (range 1-6). The median age at admission was 72 (range 41-90). Patients had a median of two major comorbidities (range 0-8). Performance status was <2 in 63% of patients (33/52). In terms of disease characteristics, International Staging Score (ISS) was stage 1 in 12% of patients, stage 2 in 38%, stage 3 in 38% and unavailable in 12%. Revised ISS (R-ISS) was stage 1 in 2% of patients, stage 2 in 44%, stage 3 in 17% and unavailable in 37%. The median line of treatment was 2 (range 0-6). Respiratory tract infection was the most common site of infection in 51% of admissions. Microbiology was negative in over half of infection admissions (50/87). Fifteen per cent (13/87) had a positive COVID-19 PCR. A positive blood culture result was identified in 8% (7/87). The median length of stay was 9 days (range 1-58). The mortality rate of admissions with infection was 17% (15/87). Overall, our real-world results show the continuing burden of infection in myeloma in the era of modern treatment. Despite the omnipresence of the COVID-19 pandemic over the last 2 and a half years, this contributed to only a small number of admissions. Infections happened in patients of all ages and many patients had good performance status, limited comorbidities and intermediate risk disease. The mortality rate of our cohort was surprisingly high at 17%. In summary, infection remains a major complication of myeloma. Given our results we now plan a trial of prophylactic antibiotics for patients on active treatment.